How much water is in the cloud?

The water content in the atmosphere is relatively small - about 0.001% of its total mass on our planet. Nevertheless, it is absolutely irreplaceable link of the natural water cycle.
The main source of atmospheric moisture are surface water bodies and moist soil; In addition, moisture enters the atmosphere as a result of the evaporation of water by plants, as well as the respiratory processes of living beings.
Water in the atmosphere is in all three aggregate states - gaseous (water vapor), liquid (raindrops) and solid (snow and ice crystals). Condensation of water vapor leads to the formation of clouds; The atmospheric moisture lost as a result of precipitation is replenished due to the receipt of new portions of evaporated water. Complete renewal of the composition of water in the atmosphere takes place in 9 ... 10 days. Thus, atmospheric moisture is the most active link in the cycle of water in nature.
The main amount of water vapor is concentrated in the lower layers of the air envelope - in the troposphere, at an altitude of up to several thousand meters, and almost the entire mass of clouds is there. The clouds appear less often in the stratosphere (at an altitude of about 25 km above the Earth). They are called pearlescent. Even higher, in the layers of the mesopause, at a distance of 50 ... 80 km from the Earth, occasionally there are noctilucent clouds. It is known that they consist of ice crystals and arise when the temperature in the mesopause drops to -80 ° C. Their formation is associated with an interesting phenomenon - the pulsation of the atmosphere under the action of tidal gravitational waves caused by the Moon.
With apparent lightness and airiness, clouds contain a significant amount of water. The water content of the clouds, that is, the water content of water in 1 m3, varies from 10 to 0.1 g or less. Since the volumes of clouds are very large (tens of cubic kilometers), even one cloud can contain hundreds of tons of water in the form of drops or ice crystals. These giant water masses are continuously carried by air currents above the Earth's surface, causing a redistribution of water and heat on it. Since water has an extremely high specific heat, evaporation from the surface of reservoirs, from the soil, transpiration of plants absorb up to 70% of the energy received by the Earth from the Sun. The amount of heat expended in evaporation (the latent heat of vaporization) comes along with the water vapor into the atmosphere and is released there during its condensation and the formation of clouds. As a result, the temperature of the water surfaces and the adjacent air layer is noticeably reduced, so near water in the warm season is much cooler than in the continental regions that receive the same amount of solar energy.

The mass of clouds and water vapor contained in the atmosphere significantly influence the radiation regime of the planet: they absorb and reflect the excess of solar radiation, and thus, to a certain extent, its flow to the Earth is regulated. At the same time, the clouds screen the opposing heat fluxes coming from the Earth's surface, reducing heat loss to the interplanetary space. From all this, the weather-forming function of atmospheric moisture is combined.

Photographer Anna Anikina